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Asociación Mexicana de Ortopedia Maxilar A.C. |
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CIRUGIA ORTOGNATICA |
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23-26 de Nov. del 2000, Acapualco Gro. M.exico 5a Reunión de Ortopedia dentofacial AMOM 2000
Resumen de Conferecias
Hamburgo, Alemania
Concepts in Orthognathic Surgery. Recent Progress.
Orthognathic surgery is performed by mandibular corrections, midfacial osteotomies and a combination of both, which means bimaxillary surgery.
Recent developments in surgical techniques, miniplate-and microplate fixation of bony segments have improved patients benefits and surgical potentials. Furthermore they have decreased surgical risks and complications in a remarkable way. Last but not least plate-fixation techniques have established much better control for functional acting forces against relapse tendencies and dysfunction.
Mostly all mandibular corrections in all three planes (sagital, vertical and transverse) can be achieved by using three surgical techniques, shich are some sort of classical procedures:
- The sagittal split osteotomy of the ascending ramus,
- The vertical-oblique osteotomy of the ascending ramus and
- The mandibular-body osteotomy (DELAIRE/PENINSULA).
Corrections of the entire mandibular body should be preferred since orthodontic treatment using fixed appliances can solve the vast majority of all dento-alveolar disorders in a perfect way. Smaller segmental osteotomies of the alveolar bone should be rejected because of higher risks, unfavorable results and the inability to correct disharmonies of the facial profile. Intermaxillary fixation during the postoperative period is not longer necessary, except for vertical-obliques surgical techniques.
Midfacial osteotomies are usually performed at the Le FORT I, II and III level, which is common for classifying midfacial fractures. While the Le FORT I-level osteotomy can solve the majority of all midfacial corrections, the Le Fort II and III - procedure are confined to rare craniofacial syndromes such as
TREACHER-COLLINS or CROUZON.
Since W. BELL (1973 / 1975) has established basic knowledge about the biological basis and blood supply of the osteotomized maxilla, we are able to move and rotate the maxilla in nearly all desired directions, not only in common cases of dysgnathia but also in CLP patients.
Bimaxillary corrections as a simultaneous procedure in hypotensive anesthesia are indicated in almost 60% of all orthognathic surgery cases. Hypotension of blood pressure during maxillary and bimaxillary procedures does decrease blood loss tremendously, cares for etter vision and decreases operation time. Bimaxillary transverse asymmetries,
oblique occlusal plane problems, open inter-basal constellations, vertical excess syndromes and short-faces syndromes should be corrected in using bimaxillary techniques.
Furthermore long-term stability after corrections of the facial profile is an important aspect, which needs a follow up control of all patients of at least 1 year after treatment is fineshed. Every orthognathic team should be aware of the patient's basic motivations to undergo treatment, which is lasting for at least 2 years or more in order to meet the patients' desires of our in a likely perfect way. Not only functional problems but particular aesthetic aspects
are playing an important role.
The lecture will be split up into three parts that emphasize on the three different main methods listed above.
